The present invention relates to water pressure systems for water wells, and more particularly, to a pressure tank installed underground within the well casing of a well for storing water under pressure for distribution and use.
A typical water pressure system for residential use is established by first drilling a hole in the ground in search of water from a water bearing aquifer. Once water is reached by the drill, a well casing is inserted into the bore hole to preserve the sides of the well. A submersible pump is then inserted into the well below the water level to pump water from the aquifer. One end of a drop pipe is attached to the submersible pump to draw water out of the well. The other end of the drop pipe is attached to a pitless adapter, which is attached to a discharge pipe for carrying water to a pressure tank located outside above ground or inside a building.
The pressure tank holds a reserve supply of water under pressure within the tank. A pressure switch coupled to the tank is used to maintain water pressure in the tank between a minimum value and a maximum value. The water is stored in the tank under pressure until it is needed. As water is drawn from the tank, the pressure in the tank decreases. The pressure switch activates the submersible pump to pump water into the tank when the water pressure in the tank drops below the minimum value. As water is pumped back into the tank, pressure in the tank increases to the maximum value. When the pressure reaches the maximum value, the pressure switch stops the pump from pumping water into the tank.
Pressure tanks are normally of substantial size, and consequently are limited to above ground installations in most water pressure systems. Typically, pressure tanks are installed outside above ground, in the basement of a house or in a separate building to protect it from the elements. Adverse weather conditions can effect the reliability of a pressure tank in cold weather climates. During the winter months, the pressure tanks must be protected from the cold and snow. Therefore, the pressure tanks for use in cold weather climates are either installed in a basement or in an insulated building above ground.
However, there are problems associated with above ground installations of pressure tanks. The large pressure tanks are usually quite expensive, cumbersome and difficult to install. The installation of a pressure tank above ground in cold weather climates may lead to freezing problems that require the tank be wrapped in insulation and heat tape or require the tank be installed in the basement of a house or a separate insulated building. Installation of a pressure tank in the basement or other area of a house takes up valuable space in the home. Installation of a pressure tank in a separate insulated building would require construction of the building. Thus, the installation of a pressure tank is often quite difficult and time-consuming.
Water pressure tanks installed underground are known in the art. For example, U.S. Pat. No. 3,394,733 to Jacuzzi discloses an airless water pressure system utilizing an underground pressure tank. The pressure tank of this invention includes an expansible tube installed around a pipe having openings therein to transfer liquid from the pipe to the expansible tube. The tube is clamped at each end to allow the liquid under pressure to cause expansion of the tube. However, the clamped ends of the tube have been known to fail under pressure from the liquid. In another patent to Jacuzzi, U.S. Pat. No. 3,442,292 discloses a pressure tank installed underground in a well, having water flowing into the pressure tank around an air filled bladder. The problem with this patented invention is the pressure tank is positioned at the top of the well, which could cause freezing problems in cold climates.
Accordingly, there is a need for a water pressure system that allows for installation of a pressure tank underground in the well casing of a well that is less expensive, easier to install and maintain, and more reliable than prior art water pressure systems.